How to take corn yields higher

• Growers should challenge themselves to become students of the crop they grow.

• When a company sells you a bag of seed, there are 500 bushels per acre locked up in that bag. Think about what the genetics are and what the yield potential is.

• Reaching the next level of production always means making adjustments that benefit both your production and your bottom line.

What does it take to get to the next level of corn production?

In simple numbers, if you’re a 185-bushel irrigated grower, it takes about 250 bushels. If you’re a 250 to 270-bushel grower, it takes about 300 to 320 bushels per acre.

And if you’re already at 350 bushels per acre, you might want to think about going for 400 bushels.

But it’s much more complex than just setting numerical goals. It requires looking closely at your crop management and making improvements wherever possible, says Dewey Lee, University of Georgia Extension small grains agronomist.

Rather than discussing data or research, Lee told the audience at this year’s Georgia Corn Short Course that he wanted to focus more on philosophy — the philosophy of taking your corn production to the next level.

“There are things you can do to affect the growth of the plant, such as reducing heat and drought stress and nutrient stress. We increase light utilization by early planting, by using a starter fertilizer, and maybe by increasing the plant population and getting uniform emergence and tighter row spacings,” he says.

Reducing stress is very important, says Lee. “Know what’s going on in the plant. If you don’t know what’s going on in the plant, then how do you know how to address something, and how do you take it to the next level?”

Disease and insect control, fertilization and irrigation all are important factors in managing a corn crop, he adds.

“It’s difficult to irrigate to meet the crop’s needs during a La Niña year, and you may not have a system that can supply all of your water needs. If that’s the case, then you need to determine the yield level that you can sustain and manage it that way,” he says.

Lee noted that Randy Dowdy of Georgia had the second-highest corn yields in the United States in 2011 in the National Corn Growers Association Yield Contest at 364 bushels per acre. “He did it with some of the sorriest soils in the state and on rolling land. (To read about how Randy Dowdy achieved his high yields, visit http://southeastfarmpress.com/grains/georgia-yield-champ-student-growing-corn-0).

“It’s a matter of being able to evaluate your capabilities and your management style. Carefully critique what you’ve been doing. If you’re stuck on 180 or 200 bushels, we’ve got better hybrids and better irrigation systems, so what is it in that formula that you might need to improve?”

Become student of the crop

Lee says growers should challenge themselves to become students of the crop they grow, whatever that crop may be. “Learn how that plant grows, and learn everything you can about your crop. Focus on how to positively affect the growth of the plant.”

In many cases, he says, growers aren’t “keeping” the yield potential of the hybrids they’re selecting.

“There are 500 bushels of corn in that seed bag, on a per-acre basis. When a company sells you a bag of seed, there are 500 bushels per acre locked up in that bag. Think about what the genetics are and what the yield potential is.

“I want you to begin by thinking about how to keep that yield, not how to increase it. The yield’s already there. If you start thinking about how you can keep the yield that’s in the bag, your production will move to the next level,” he says.

Looking at the University of Georgia’s corn variety trials from this past year, there was a wide range throughout the state, says Lee.

“In our tests, there are 50 to 60 bushels between hybrids. So your decision to choose a hybrid is exceedingly important. Choose those that match your management style and that fit your production level, and then make sure you continually incorporate those genetics on your farm.”

Use the genetic traits that’ll benefit you economically, advises Lee.

Growers should be pre-planning their production rather than just following the same routine from previous years, he says.

“Many hybrids today are responding to higher plant populations as long as you keep them watered, but this may require a change in production methods.”

In addition to routine soil testing, growers also should conduct in-season tissue analysis to make sure their crops are responding to what they’ve applied.

“It also can give you an indication what else you might need to do. Maybe you should conduct a timely tissue analysis early in the season to make sure the crop is utilizing the nutrients you’ve applied. Perhaps you need to apply something through the system.

“As we make higher and higher yields, we begin to learn we don’t know enough, and we begin to realize that maybe our sufficiency levels aren’t high enough. We can see this throughout the season.”

Growers with irrigation should regularly check the efficiency of their equipment, says Lee, and replace their nozzles if needed.

Always make adjustments

Reaching the next level of production, he says, always means making adjustments that benefit both your production and your bottom line.

“I’d like for you to take a field this year where you can deliver the water the crop requires. Use a top hybrid and increase your plant population. If you’re at a 30,000 to 32,000 plant population, go to 34,000 to 36,000 plants.

“In this field, plant slowly and check your seeding rating and depth, stay at 1.5 to 2 inches deep. But more importantly, slow down. You’re not rushing so you can plant cotton or peanuts. You don’t have the competition for your time when you’re planting corn.

“Take your time, use more fuel, and get a nice, even distribution. Improve the uniformity of your stand. Get the crop up and growing all at the same time and maximize light reflection. If you’ve got one plant up earlier than the next plant, it’ll start shading that smaller plant. Reduce light interception — every plant in that field is important.”

Lee says growers should be using a starter fertilizer with N, P and K.

“One of the things we might be missing in Georgia is potash at planting. I see a real value when it comes to improving plant health and root production and mass.”

Target your fertility with a yield goal, he says, and stay ahead of early stress.

“Poultry litter is an excellent substitution. Use 2 to 4 tons, and use your analysis to determine the amount to credit your nutrients. Give yourself about 60 to 65 percent credit of nitrogen in the season — not at planting time — and 80 to 85 percent of phosphate and potash, in the season. If you’re using poultry litter, you need to be using a starter fertilizer.”

“We’ve got lots of good chemistries. When you make these treatments early, our trials show that with glyphosate and atrazine, you get about 95-percent effective control. If you wait to make those applications, you’ll lose control of the weeds and lose yields.”

There are several ways of gaining yield in a corn crop, says Lee.

“If you find a deficiency in a tissue analysis, it’ll make you between 5 and 30 bushels per acre. If you scout for disease, it can make you 5 to 25 bushels per acre. Treating for nematodes can gain you 10 to 40 bushels per acre. Insect control can gain you 5 to 15 bushels, and timely irrigation can gain you 30 to 100 bushels per acre.

“Don’t leave these bushels in the field. And we’ve learned that you can do this efficiently. We’ve still got a good enough price for corn to capture and maintain that yield.”

The last thing that can take money from you is aflatoxin, says Lee.

“You can save a lot of money by reducing aflatoxin problems, and this can be done by reducing the various stresses on the corn crop.”